11399978 has 4 divisors (see below), whose sum is σ = 17099970. Its totient is φ = 5699988.

The previous prime is 11399977. The next prime is 11399989. The reversal of 11399978 is 87999311.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 8720209 + 2679769 = 2953^2 + 1637^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (11399977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2849993 + ... + 2849996.

Almost surely, 2^11399978 is an apocalyptic number.

11399978 is a deficient number, since it is larger than the sum of its proper divisors (5699992).

11399978 is an equidigital number, since it uses as much as digits as its factorization.

11399978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5699991.

The product of its digits is 122472, while the sum is 47.

The square root of 11399978 is about 3376.3853453064. The cubic root of 11399978 is about 225.0615666911.

The spelling of 11399978 in words is "eleven million, three hundred ninety-nine thousand, nine hundred seventy-eight".